According to a study published in the journal BMC Public Health, children as young as 10- and 11-years-old already have notions about the ideal body. An analysis of more than 4,000 students from Nova Scotia revealed that young girls’ happiness with their body image is directly linked to how thin they are. Boys, on the other hand, were happiest when they were neither too lean, nor too heavy.

Given that dissatisfaction with body image is strongly linked with an increased risk for eating disorders, the researchers were particularly concerned to find that the perception of perfection began at such a young age. Overall, 7.3% of the girls included in the study reported that they didn’t like they way they looked, but that increased proportionately as girls’ weight, measured by body mass index (BMI), went up. For girls with normal body weight, 5.7% reported being unhappy with their bodies, among those who were overweight, 10.4% did, and among girls who were categorized as obese, 13.1% were unhappy with how they looked. For girls, the researchers noted, every one unit increase in BMI measurement indicated about an 8% increase in body dissatisfaction.

What’s more, among the girls, but not the boys, those who had lower levels of educational achievement or lived in more rural areas were more likely to report feeling unhappy with their bodies.

Among boys, reported dissatisfaction was slightly higher than for girls, 7.8% compared with 7.3%, but unlike with the girls, their level of contentment did not fall in direct association with increasing body weight. Instead, boys were unhappy if they perceived themselves as too skinny or as overweight. Yet, similarly to the girls, as BMI increased to overweight or obese, there was also a trend of increasing dissatisfaction among the boys. For boys of normal weight, 7.6% reported not liking how they look, of those who were overweight, 8.4% did, and of those considered obese, 8.1% did.

Previous studies have shown that early, school-based intervention to teach children about healthy body weight and body image have actually achieved some success. Considering the prevalence of childhood overweight—which now effects a third of American children, and more than a quarter of Canadian children—understanding how kids perceive themselves, and helping them to build confidence by building healthy behaviors may be vital not only for combating the obesity epidemic, but also diminishing its concurrent health problems, which range from diabetes to depression.